Philip Seymour Hoffman, the Oscar-winning actor who played everything from a maverick CIA agent to a drag queen to a Catholic priest, has died. He was 46.

Police sources say Hoffman was found unconscious at around 11:15 this morning on the bathroom floor of his New York apartment at 35 Bethune St. in the West Village neighborhood of Manhattan by friend and screenwriter David Katz, who called 911. He was pronounced dead at the scene.

The cause of death has not yet been determined, but a law enforcement official tells ABC News heroin was found at the scene and a hypodermic needle was sticking out of Hoffman's arm. The New York Police Department is continuing to investigate.

Results from the NYC Office of Chief Medical Examiner on the exact cause of death are expected on Monday.

Hoffman's family released the following statement on the actor's untimely death this afternoon:

"We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone. This is a tragic and sudden loss and we ask that you respect our privacy during this time of grieving. Please keep Phil in your thoughts and prayers."

Hoffman won the Best Actor Academy Award and the Golden Globe Best Performance by an Actor in a Motion Picture Drama for his leading role in the 2005 film "Capote," which detailed the five-year period during which author Truman Capote penned "In Cold Blood."

He was nominated for three Best Supporting Actor Oscars, for "The Master," "Doubt," and "Charlie Wilson's War."

The second of four children, Hoffman was born on July 23, 1967 in Fairport, N.Y., to mother Marilyn O'Connor (née Loucks), a lawyer, and father Gordon Stowell Hoffman who worked for Xerox.

He graduated with a BFA in drama from New York University's Tisch School of the Arts in 1989 and began his film career in 1991, starring in his debut role in the indie production "Triple Bogey on a Par Five Hole."

Hoffman's breakthrough role came in Paul Thomas Anderson's "Boogie Nights" (1997), after which he quickly became known for his leading and supporting roles on the big screen, including Todd Solondz's "Happiness" (1998), "Flawless" (1999), "The Talented Mr. Ripley" (1999), Paul Thomas Anderson's "Magnolia" (1999), "Almost Famous" (2000) and "State and Main" (2000).

In 2005, Hoffman starred in the role that would lead him to win the Los Angeles Film Critics Award as Best Actor for his performance in "Capote." The next year, he won an Oscar for the same part.

He also proved himself a capable theater actor on Broadway, receiving two Tony nominations for Best Actor in 2000 for a revival of Sam Shepard's "True West" and again in 2003 for a revival of Eugene O'Neill's "Long Day's Journey into Night."

In 2012, Hoffman starred as Willy Loman in the Broadway revival of Arthur Miller's Death of a Salesman, receiving rave reviews from critics and his third Tony Award nomination as Best Leading Actor in a Play.

Hoffman made his film directorial debut in 2010 with "Jack Goes Boating." More recently Hoffman appeared in Hunger Games: Catching Fire.

Hoffman has previously been in rehab for drug and alcohol addiction. In his early twenties, Hoffman said he started abusing drugs not long after graduating from his degree at NYU.

"I went [to rehab], I got sober when I was 22 years old," Hoffman revealed during a 2006 interview with CBS News' "60 Minutes." "You get panicked ... and I got panicked for my life."

He also said he was lucky he got sober before becoming famous and had the money to feed his addiction.

"I have so much empathy for these young actors that are 19 and all of a sudden they're beautiful and famous and rich," he said in the interview. "I'm like, 'Oh my God, I'd be dead."'

The actor said he kicked the habit for 23 years and had remained sober until May 2013 when he briefly relapsed and returned to rehab after admitting to snorting heroin.

Hoffman's death comes one day after representatives issued a statement denying a report about the actor's death earlier in the week.

He is succeeded by his girlfriend, costume designer Mimi O'Donnell, their son, Cooper, 10 and two daughters, Tallulah, 7, and Willa, 5.